This invention relates generally to the problem of attaining secure retention for lenses which are used to hold in place a designation card of paper or plastic containing written, typed or printed information that may require periodic updating. One area of use involves telephone housings, of which some models include a shallow recess in one surface intended to receive the information-bearing card. In the field of this invention, the word xe2x80x9clensxe2x80x9d (pl. lenses) designates a flat, translucent, resilient cover or cap, and does not include a component with magnifying properties.
Prior to the present development, injection molded lenses and non-injection-molded lenses have been used. Lenses of both kinds require expensive tooling and high part costs. Also, due to the inherent properties of the injection molding process, many parts contain flaws and are subsequently rejected, so as not to compromise the overall impression of quality in the products. The non-injection-molded lenses previously employed are very difficult to remove and typically require the use of an appropriate tool.
In order to hold the lens and the underlying information card securely during regular use, transportation or adverse environmental conditions, a device is provided which requires only a low-actuating force, and is easily understood in terms of the method for removal and assembly of the components. This ease of use promotes regular updating of the card, allowing accurate information to be presented to the user.
More particularly, this invention provides a flat, substantially transparent lens lying generally in a substantially flat plane, the lens being adapted to retain a designation card within a recess in a surface, the lens being made from resiliently flexible sheet plastic and having first and second opposed ends, first means at said first end by which the first end can be removably retained in the recess, and second means at said second end by which the second end can be removably retained in the recess; said first means comprising a tab integral with the plastic of the lens, the tab extending from an attachment end where it joins the lens, thence extending generally athwart the plane of the lens to a geniculation spaced away from said plane, at which geniculation the tab generally reverses direction and extends generally athwart the plane of the lens to return generally to said plane, where it terminates in a finger-grip by which the lens can be released from, or snapped into, the recess.
Further, this invention provides in combination: a surface having a recess adapted to receive a designation card, and a lens extending in a substantially flat plane, the lens being adapted to retain a designation card within said recess, the lens being of resiliently flexible sheet plastic and having first and second opposed ends, first retention means at said first end by which the first end can be removably retained in the recess, and second retention means at said second end by which the second end can be removably retained in the recess; said first means comprising a tab integral with the plastic of the lens, the tab extending from an attachment end where it joins the lens, thence generally athwart the plane of the lens to a geniculation spaced away from said plane, at which geniculation the tab generally reverses direction and extends generally athwart the plane of the lens to return generally to said plane, where it terminates in a finger-grip by which the lens can be released from, or snapped into, the recess.